Process of producing pure soaps from oxidized nonaromatic hydrocarbons



Patented Mar. 9, 1937 UNITED STATES PATENT OFFICE FROM OXIDIZEDDROCARBONS NONAROMATIC HY- Hans Franzen, Mannheim, Germany, assignor toFarbenindustrie Aktiengesellschaft,

Frankfort-on-the-Main, Germany No Drawing. Application October 17, 1934,Serial No. 748,717. In Germany October 19, 1933 4 Claims.

The present invention relates to the production of wetting, washing anddispersing agents.

The soap solutions obtained by the saponification of the oxidationproducts of hydrocarbons 5 of high molecular weight, as for example ofparaffin waxes or mineral oil fractions, cannot be directly worked upinto useful wetting, washing and dispersing agents because they are darkin color and have an undesirable odor. It is therefore necessary tosubject them. to a very troublesome purification process before theirfurther working up, as for example by precipitating the fatty acids fromthe soap solutions by means of mineral acids, purifying the fatty acidsby distillation and then reconverting them into soaps with alkali.Considerable waste of valuable material, alkali and acid, however,always takes place.

I have now found that very pure soaps (which are directly employable aswetting, washing, dispersing and like agents) are obtained in a simplemanner by dissolving oxidation products of,hy-

drocarbons of high molecular weight in a waterinsoluble solvent,treating the solution obtained with an aqueous solution of awater-soluble alkaline-reacting substance (such as caustic,"

alkali, alkali metal carbonate, ammonia. or water-soluble amines),separating the aqueous solution obtained and extracting therefrom theun.-"

saponifiable constituents by means of a waterinsoluble solvent and ifdesired evaporating the resulting soap solution to dryness. Thewaterinsoluble solvent to be used for dissolving the oxidation productsmay be the same as or may be different from that to be used forextracting the non-saponifiable matter from the soap solution separated.

As initial materials may be mentioned for example oxidation products ofparaflin waxes, mineral oils or higher boiling fractions thereof as forexample petroleum or middle oils, and also the products obtained by theoxidation of destructive hydrogenation products of coals and tars.

Single solvents or mixtures of several solvents may be employed. Aswater-insoluble solvents or solvent mixtures may be mentioned benzine,benzene, cyclohexane, cyclohexanol, tetrahydronaphthalene, carbontetrachloride and mixtures of benzine and ethyl alcohol.

The solution of the oxidation products in the water-insoluble'solventsor solvent mixtures may take place at ordinary or elevated temperature.Usually it is effected at temperatures not below 20 C. The upper limitof the temperature used is the boiling point of the solvents employedand it is preferable to work near the latter temperature. The solutionsthus obtained are then treated with aqueous solutions of alkali metalhydroxides, alkali metal carbonates, ammonia or. amines, as for example'methylamine, ethylamine, dimethylamine, mono-, dior triethanolfamine.The amount of the said aqueous solutions depends on the concentration ofthe said basic substances in the aqueous solutions and on thesaponification value of theoxidation products employed. The said basicsubstances are preferably used in an excess of from about 5 to 10 percent of the theoretically required amount calculated on thesaponification value. The working temperature depends on the compositionof the oxidation'products and may be readily ascertained by a simpleexperiment. It may be desirable to work under pressure in order to avoidlosses of solvents, especially if low boiling solvents are employed.After mixing thoroughly, the whole is allowed to settle; the soapsolution is then withdr vvn. For the purpose of complete- 'ly removing teunsaponifiable constituents, the aqueous soap solution is treated witha watersired temperature under ordinary or elevated ,pressure, filteredif necessary and if desired evaporated to dryness in a suitable mannerunder ordinary or decreased pressure. The drying may be effected forexample in a roller dryer or a Krause apparatus.

The products obtained according to this invention are pale soaps whichhave practically no undesirable odor and are therefore capable ofemployment for further' Working up into shaped soaps or other washing orlike agents.

The following examples will further illustrate the nature of thisinvention but the invention is not restricted to these examples. Theparts are by weight.

Example 1:

Hard paraflin wax is oxidized by blowing with air at from to C. whileemploying 0.05 per cent of sodium palmitate and 0.05 per cent ofmanganese palmitate as catalysts for 4 hours in the usual manner. 1200parts of the resulting oxidation product, having a saponification valueof 149, are dissolved in a mixture of 2400 parts of benzine and 600parts of ethyl alcohol and intimately stirred for half an hour at atemperature of from 56 to 58 C. with a solution of 184 parts of sodiumcarbonate in 920 parts of water. The mixture is then allowed to settleand the soap insoluble solvent (or solvent mixture) at any desolution.is withdrawn. The latter is extracted with 1200 parts of benzine andevaporated to dryness in a roller dryer. A good yield of a colorless andodorless soap powder having a high wetting, foaming and washing poweris'thus obtained.

Example 2 A so-called middle oil is oxidized with air at from about toC. while adding 0.2 per cent of manganese naphthenate as a catalyst for3 hours, an oxidation product thus being obtained having asaponiflcation value of 90. 630 parts of this oxidation product aredissolved in 1200 parts of benzene and intimately stirred for half anhour at a temperature of from 40 to 45 Cl with a solution of 44 parts ofsodium hydroxide in 560 parts of water. The mixture is then allowed tosettle, the soap solution is drawn off and extracted with 600 parts ofbenzene. The soap solution thus obtained may be directly employed forwashing. It may also be evaporated to dryness by spraying in a Krauseapparatus, a yellowish odorless soap powder having a high foaming andwashing power thus being obtained.

Example 3 500 parts of the oxidation product obtained as set forth inthe first sentence of Example 1 are dissolved in about 710 parts ofdiethylether. The solution is stirred together with a solution of 200parts of triethanolamine in 1000 parts of water with the addition of 240parts of ethyl alcohol at 33 C. for 45 minutes in a closed vessel. Aftercooling, the soap layer is separated and extracted once or twice with710 parts of diethylether. The soap solution thus obtained is a highlyactive washing agent.

What I claim is:-

1. The process of producing pure soaps from oxidized non-aromatichydrocarbons of high molecular weight which comprises dissolving thesaid oxidized hydrocarbons in a water-insoluble solvent, treating thesolution obtained with an aqueous solution of a water-solublealkaline-reacting substance in the presence of a lower aliphaticalcohol, separating the aqueous solution and extracting therefrom theunsaponifiable constituents by means of a water-insoluble solvent.

2. The process of producing pure soaps from oxidized non-aromatichydrocarbons of high molecularweight which comprises dissolving the saidoxidized hydrocarbons in a water-insoluble solvent, treating thesolution obtained with an aqueous solution of a water-solublealkaline-reacting substance in the presence of a lower aliphaticalcohol, separating the aqueous solution, extracting therefrom theunsaponifiable constituents by means of a water-insoluble solvent andevaporating the said aqueous solution to dryness.

3. The process of producing pure soaps from oxidized non-aromatichydrocarbons of high molecular weight which comprises dissolving thesaid oxidized hydrocarbons in a mixture of waterinsoluble solvents,treating the solution obtained with an aqueous solution of awater-soluble alkaline-reacting substance in the presence of a loweraliphatic alcohol, separating the aqueous solution and extractingtherefrom the unsaponifiable constituents by means of a water-insolublesolvent.

4. The process of producing pure soaps from oxidized non-aromatichydrocarbons of high molecular weight which comprises dissolving thesaid oxidized hydrocarbons in a mixture of waterinsoluble solvents,treating the solution obtained with an aqueous solution of awater-soluble alkaline-reacting substance in the presence of a loweraliphatic alcohol, separating-the aqueous solution and extractingtherefrom the unsaponiflable constituents by means of a mixture ofwater-insoluble solvents.

HANS FRANZEN.

